A software metric is a standard of measure of a degree to which a software system or process possesses some property. A measurement is one way to understand how well a process is working and what a process is doing.
Software metrics can be classified into three categories:
I] Product metrics
II] Process metrics and
III] Project metrics
I] Product metrics:-
Describe the characteristics of the product such as size, complexity, design features, performance, and quality level.
Mean time to failure
Defect density
Customer problems
Customer satisfaction.
II] Process metrics:-
Can be used to improve software development and maintenance.
Examples include the
Effectiveness of defect removal during development
Pattern of testing defect arrival
The response time of the fix process
III] Project metrics:-
Describe the project characteristics and execution
Examples include the
Number of software developers
The staffing pattern over the life cycle of the software
Cost
Schedule
Productivity
Above Software Quality Metrics are measured in terms of:-
Customer satisfaction
Conformance to requirements
Quality of design
Quality of standard
Quality of performance
Software Quality Metrics are measured on following function points:-
1. Data communications
2. Distributed functions
3. Performance
4. Heavily used configuration
5. Transaction rate
6. Online data entry
7. End-user efficiency
8. Online update
9. Complex processing
10. Reusability
11. Installation ease
12. Operational ease
13. Multiple sites
14. Facilitation of change
Metrics are used to,
1. Take the decision for next phase of activities such as, estimate the cost & schedule of future projects.
2. Understand the kind of improvement required to success the project
3. Take decision on process or technology to be modified etc.